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Reaction Engineering of Direct Coal Liquefaction  [PDF]
Ken K. Robinson
Energies , 2009, DOI: 10.3390/en20400976
Abstract: Direct coal liquefaction has been studied and practiced since the 1930s. It was used in Germany during World War II to produce synthetic fuels when there was no oil allowed into the country. Since then, it has been studied in the United States and many different technologies have been investigated. Since the US is rich in coal resources, this is one way to be energy independent. Most of the development activity occurred in the 1980s and numerous technologies were studied, the most notable of these being H-Coal, Exxon Donor Solvent, Solvent Refined Coal, and Two Stage Liquefaction. The key elements of these technologies, particularly the reaction/reactor scheme, are discussed in this review.
Analysis and characterization of recycled oil from direct liquefaction of Shenhua coal

LIN Hua-lin,ZHANG De-Xiang,PENG Jun,YANG Li-jun,PAN Tie-ying,GAO Jin-sheng,
,张德祥,彭 俊,羊丽君,潘铁英,高晋生

燃料化学学报 , 2007,
Abstract: The recycled oil from coal liquefaction was separated into three fractions(saturates,aromatics and polar fraction) by liquid chromatograph according to group composition.Each fraction was analyzed qualitatively by 1H-NMR spectra,then the aromatic fraction was characterized using gas chromatograph/mass spectrometer(GC-MS).It shows that liquid chromatograph is well used to separate coal liquefaction oil with high repeatability and high recovery yield.Aromatic fraction with carbon number from C10 to C21 mainly includes dicyclic-,tricyclic-and tetracyclic-hydrogenation aromatic compounds such as tetrahydronaphthalene,hydrophenanthrene,hydropyrene and their alkyl substitution compounds and so on.
Influence of direct coal liquefaction residue on viscoelastic properties of asphalt mortar

- , 2015,
Abstract: 以SK-90沥青为基质沥青,分别制备粉胶比为1.0、煤直接液化残渣(DCLR)掺量(质量分数)分别为5%、10%、15%、20%下的DCLR改性沥青胶浆和SK-90沥青胶浆。采用动态剪切流变试验和弯曲梁流变试验,对比分析了DCLR对沥青胶浆车辙因子、疲劳因子、蠕变劲度模量和蠕变速率等因素的影响,揭示了DCLR对沥青胶浆黏弹性能的影响规律。试验结果表明:DCLR会显著增强沥青胶浆的高温性能,降低沥青胶浆的低温性能和疲劳性能; DCLR提高了沥青胶浆在高温条件下的弹性及在低温条件下的黏性; 在高DCLR掺量下,沥青胶浆的高温、低温和疲劳性能对温度的敏感度极为显著; 随着DCLR掺量的增加,沥青及胶浆的适用范围越来越窄; 从应用角度考虑,建议DCLR掺量不宜大于10%,沥青及胶浆可适用于沥青路面的中面层。
SK-90 was taken as base asphalt, filler-asphalt ratio was 1.0, the direct coal liquefaction residue(DCLR)modified asphalt mortars with the DCLR contents as 5%, 10%, 15%, 20% and SK-90 asphalt mortar were produced respectively. The influences of DCLR on asphalt mortar rut factor, fatigue factor, creep stiffness modulus and creep rate were compared by dynamic shear rheometer(DSR)and bending beam rheometer(BBR)tests. The influence rule of DCLR on the viscoelastic properties of asphalt mortar was analyzed. Test result indicates that DCLR can significantly improve the high-temperature properties of asphalt mortar, reduce its low-temperature and fatigue properties. DCLR also increases the elastic properties of asphalt mortar at high temperature and the viscous properties at low temperature. The high-temperature, low-temperature and fatigue properties of asphalt mortar with high DCLR content are very sensitive to temperature. With the increase of DCLR content, the application scopes of asphalt and asphalt mortar become more and more narrow. Therefore, in the view of application, the content of DCLR is recommended to be less than 10%, and the asphalt and asphalt mortar can be applied for middle surface layer of asphalt pavement. 11 tabs, 4 figs, 23 refs
K. Pawani,Sachidanand Ojha,Rama Mishra
International Journal of Advanced Technology & Engineering Research , 2012,
Abstract: The ever increasing progress of high-voltage high-power fully-controlled semiconductor technology continue to have a significant impact on the development of advance power electronic apparatus used to support optimized operation and efficient management of electrical grids, which in many cas-es are fully or partially deregulated networks. Developments advance both the high voltage direct-current (HVDC) power transmission and the flexibility alternating current transmis-sion system (FACTS) technologies. In this paper, an over-view of the recent advances in the area of voltage source converter (VSC) HVDC technology is provided. Selected key multilevel converter topologies are presented. Control & modeling method are discussed. It is confirmed that the con-tinuous development of power electronics present cost effec-tive opportunities for the utilities to exploit and HVDC re-mains a key technology. In particular, VSC-HVDC can ad-dress not only conventional network issues such as bulk power transmission, asynchronous network interconnection, back-to-back AC system linking and voltage/stability sup-port to mention a few, but also niche markets such as the integration of large scale renewable energy sources with the grid.
Hydrotreatment of heavy oil from coal liquefaction on Sulfided Ni - W Catalysts
Lei, Zhi-ping;Gao, Li-juan;Shui, Heng-fu;Ren, Shi-biao;Wang, Zhi-cai;Gang, Kang-shi;
Journal of the Brazilian Chemical Society , 2011, DOI: 10.1590/S0103-50532011000600017
Abstract: heavy oil (distillation temperature: 320-340 oc) derived from the direct coal liquefaction process using shengli coal were hydrotreated using sulfided ni-mo/al2o3, ni-w/al2o3, and ni-w/sio2 catalysts respectively. the sulfided catalysts were characterized by bet, xrd, h2-tpr and nh3-tpd respectively. the evaluations of the hydrodenitrogenation (hdn) and hydrodearomatization (hda) properties of heavy oil on the three catalysts were carried out at 400 oc and 5.0 mpa initial h2 pressure. the w-based catalysts displayed better performances than mo-based catalysts for the hdn and hda reactions. al2o3 supported catalysts were found to have higher catalytic activities than on sio2 supported ones. the activities of sulfided catalysts were associated mainly with the nature of active sites, acidity, metal sulfide crystallite size and the amount of the reducible sulfur species of metal sulfide.
Recent advances in direct C–H arylation: Methodology, selectivity and mechanism in oxazole series  [cached]
Cécile Verrier,Pierrik Lassalas,Laure Théveau,Guy Quéguiner
Beilstein Journal of Organic Chemistry , 2011, DOI: 10.3762/bjoc.7.187
Abstract: Catalytic direct (hetero)arylation of (hetero)arenes is an attractive alternative to traditional Kumada, Stille, Negishi and Suzuki–Miyaura cross-coupling reactions, notably as it avoids the prior preparation and isolation of (hetero)arylmetals. Developments of this methodology in the oxazole series are reviewed in this article. Methodologies, selectivity, mechanism and future aspects are presented.
Co-liquefaction of Coal and Used Tire in Supercritical Water  [PDF]
Kwanruthai Onsri, Pattarapan Prasassarakich, Somkiat Ngamprasertsith
Energy and Power Engineering (EPE) , 2010, DOI: 10.4236/epe.2010.22014
Abstract: The co-liquefaction of lignite coal and used tire was performed in a 250-ml batch reactor, in supercritical water under a nitrogen atmosphere to investigate the effects of temperature (380-440℃), water/feedstock ratio (4/1-10/1 (wt./wt.)) and the % used tire content in the feedstock (0-100 wt.%) on the conversion efficiency, liquid yield and oil composition attained. The maximum conversion and oil yield were 67 and 50%, respectively, obtained at 400℃ at 1 min, with water/feedstock ratio of 10/1 and 80% used tire content. The distillation characteristics of the oil products, analyzed by simulated distillation gas chromatography, revealed that the oil composition depended significantly on the reaction temperature. The co-liquefaction of coal and used tire yielded a synergistically increased level of oil production. Moreover, the total conversion level obtained with co-liquefaction alone was almost equal to those obtained in the presence of either Fe2O3 or NiMo as catalysts, under the same conditions. Therefore, supercritical water is a good medium for the dissolution of the volatile matter from a coal and used tire matrix.
Co-liquefaction of Enriched Coal Maceral Constituents and Sawdust
WANG Yang,LI Ting-chen,REN Zheng-wei,YAN Yong-jie,
WANG Yang 王炀
,LI Ting-chen 李庭琛,REN Zheng-wei 任铮伟

过程工程学报 , 2002,
Abstract: Co-liquefaction of coal and sawdust was studied in the presence of hydrogen-donor solvent, tetralin. Coal samples were prepared through floatation of the Xinwen coal, followed by enrichment of maceral constituents. Sample I was rich in vitrinite and Sample II fusinite. Effects of reactiontemperature, time and initial cold H2 pressure were studied on conversion, yield, especially oil yield,through comparison between these two samples. Because it is more difficult to be liquefied, Sample II, is greatly affected by changes in temperature and time. However, it is almost independent of change ininitial cold H2 pressure, owing to the role of tetralin as hydrogen vehicle. Certain product(s) formed from thermolysis of sawdust can help hydrogenation of the intermediate (asphaltene and preasphaltene) infurther forming oil products.
Combustion performance of the blend of lignite and residues of coal liquefaction in thermal-banlance

FANG Lei,ZHOU Jun-hu,ZHOU Zhi-jun,LIU Jian-zhong,CEN Ke-fa,
方 磊

燃料化学学报 , 2006,
Abstract: The combustion performance of the blend of lignite and residue from Shenhua coal liquefaction was studied. It is found that the DTG plot for the combustion of residue of coal liquefaction has three characteristic peaks, while the DTG plot of lignite combustion has one characteristic peak. With the decreasing of the blending ratio of coal liquefaction residue to lignite the three characteristic peaks become faintness. The combustion activation energies of blended coals are calculated. Compared with the blended coals, the coal liquefaction residue has the biggest activation energy, but the lignite has the lowest one. With the blending ratio decreasing the activation energy and ignite temperature of blends decrease slightly. The maximum weight loss rate DTGmax for coal liquefaction residue is bigger than that for lignite.
Recent advances in the management of breathlessness  [cached]
Breaden Katrina
Indian Journal of Palliative Care , 2011,
Abstract: Breathlessness is a frightening symptom to both witness and experience. It is common in many conditions, especially in the palliative setting, profoundly affecting the quality of the person′s life. The purpose of this article is to provide an overview of the recent advances in the management of breathlessness in the areas of, knowledge of disease trajectories, assessment, pharmacological and non-pharmacological interventions and the use of oxygen.
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